


Of Rats and Broomsticks

by FantasticNumberNine



Series: John Watson and the Prisoner of Azkaban [8]
Category: Harry Potter - J. K. Rowling, Sherlock (TV)
Genre: AU, Crossover, Gen, Lots of shouting, Potterlock, Quidditch match, brooms are confiscated, john discovers girls, jurys out on that, mostly at Mycroft, or are eaten, rats vanish mysteriously, still working on discovering boys
Language: English
Status: Completed
Published: 2015-06-05
Updated: 2015-06-05
Packaged: 2018-04-02 23:34:20
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,212
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4078090
Author URL: https://archiveofourown.org/users/FantasticNumberNine/pseuds/FantasticNumberNine
Summary: <blockquote class="userstuff">
              <p>Gryffindor's match against Ravenclaw approaches, and John still hasn't ordered a new broom since Mycroft got it confiscated at Christmas, and Greg's pet rat Scabbers is missing, suspected dead, eaten by Mycroft's cat, Crookshanks. Friendships are tested, and perhaps irrevocably broken...</p>
            </blockquote>





	Of Rats and Broomsticks

**Author's Note:**

> *disclaimer*
> 
> Yeah, genuinely sorry about the wait for this. But it's here now! Complete with over dramatic summary!

John knew, rationally, that Mycroft had meant well. But it was hard to feel rational when the best broom in the world was unceremoniously taken away to be stripped down. Greg thought it was nothing less than criminal, and Mycroft avoided the common room for the rest of the holiday. 

Classes started up again the shortly after the New Year, and John stayed after in Defense to schedule his anti-dementor lesson with Lupin.

"Still looks a bit ill, doesn't he?" Greg commented as they headed down to dinner. "What d'you reckon's wrong with him?"

There was a quiet scoffing sound behind them, Mycroft was sitting at the feet of a suit of armor, shoving an impossible quantity of books into his bag.

"What're you scoffing at us for?" Greg asked irritably.

"Nothing," said Mycroft loftily, and gave up trying to close his bag and heaved it over his shoulder.

"It's definitely something. I said I wonder what's wrong with Lupin, and you--"

"Well, it's _obvious_ , isn't it?" Mycroft said, smugly superior.

Greg snorted, "If you don't want to tell us, you don't have to."

Mycroft smirked and swept past them regally.

"He doesn't know. He's just trying to get us to talk to him again," Greg stared resentfully after Mycroft; John sighed.

John finally began his anti-dementor lessons with Professor Lupin, but despite occasionally succeeding in conjuring a silvery whisp of light, he felt very much that he was making very little progress. 

On top of his weekly sessions with Professor Lupin, Oliver Wood had upped the number of nightly quidditch practice to five (Slytherin's narrow win over Ravenclaw was supposedly a good thing), and John was left with one night to do all of his homework. Only Mycroft appeared more overworked to John; every night John came back to the common room, Mycroft was sat in a corner, surrounded by stacks of books, charts and diagrams, with ink stains up to his usually immaculate elbows. 

"How's he doing it, then?"

Greg was staring at Mycroft, again, over the top of his potions book as he sat beside John--who was himself preoccupied with his essay on Undetectable Poisons for Snape.

John hm'd distractedly, flipping the pages of his own potions text in search of a reference.

"I heard him talking to Professor Babbling, about her Ancient Runes lesson from yesterday, but Myc was with us in Divination yesterday! And Ernie McMillan told me he's never missed a Muggle Studies class, which is ridiculous, because you said you were still sitting with him for Arithmancy--which is your choice, really, mate, but why put up with that tosser more--"

John screwed his eyes shut and tried very hard not to snap his quill when Greg's rambling tirade was interrupted by Wood, who bore no _good_ news about his Firebolt. 

The arrival of February was mostly unnoticed, except by John, who had yet to order a new broom for the quickly approaching match against Ravenclaw. And his most recent lesson and conversation with Professor Lupin had done nothing to help his confidence.

It was a very distracted John who collided with Professor McGonagall on his way back to Gryffindor Tower.

"Do watch where you're going, Watson!"

"Sorry, Professor--"

And then his jaw dropped, as he saw what she was holding out to him--his Firebolt was in her hands, as magnificent as ever!

"I can have it back?" John asked weakly. "Are you serious?"

John was speechless as he carried his Firebolt upstairs. Greg met him partway there, a broad grin on his face.

"She gave it back! Brilliant! John, listen, could I have a go on it? Tomorrow? After your practice?" Greg was bouncing around John as they made their way to the Tower, narrowly missing several collisions with multiple suits of armor--who shook their heads in exasperation after the boys.

"Yeah, definitely!" John felt lighter than he had since their shouting match with Mycroft, speaking of which-- "We should make up with Mycroft. He _was_ only trying to help."

"Yeah, fine."

John and Greg found Molly arguing with Sir Cadogan outside their Tower ("Maybe if you didn't change the password every half hour, we wouldn't _need_ to write them down, you incompetent twat!") and the shouting ceased only when Greg managed to unfold his sheet of passwords for the week and John threw his shoe at the knight.

"Oddsbodikins!" Greg hollered. "Merlin, but he's annoying."

The scene was immediately forgotten as they climbed into Gryffindor and nearly the entire House mobbed John and his gleaming Firebolt. It took him and Greg ten minutes to fight their way over to Mycroft, who, as had become customary of late, was working alone on ten separate projects simultaneously.

"Mycroft!" John grinned down at him, brandishing the Firebolt cheerfully. "I got it back!"

"See, Myc! There wasn't anything wrong with--oomf!" 

John elbowed Greg.

Mycroft glared up at Greg, his teeth grinding visibly, before turning to smile tiredly at John. "Wonderful, and now you know that it's safe."

"Yeah. Em. I should probably put it upstairs--"

"I'll take it!" Greg said quickly. "I've got to give Scabbers his tonic, anyways, can I?"

John watched as Greg disappeared up to their dorm, holding the Firebolt reverently.

"Eh, mind if I sit?"

"Are you going to go on about how wrong I evidently was?" Mycroft asked quietly, turning a page of his Arithmancy text idly.

"Er, no. I was thinking we could just forget it, it turned out alright, in the end."

Mycroft scoffed under his breath, but cleared a spot on the couch from a frightening stack of notes.

"I also had a question about the homework Professor Sinistra assigned yesterday--"

"Ah, the Knut drops," Mycroft laughed.

John grinned and snatched Mycroft's Arithmancy text, flipping back a few pages. "It's about the properties of three--"

A strangled yell echoed down the boys' staircase, and the whole common room fell silent. Then Greg came pounding down into view, a bed sheet dragging behind him.

"LOOK!" He bellowed, stalking over to where John and Mycroft were sitting. "LOOK!" He shouted again, throwing the sheet at Mycroft.

Mycroft stared at Greg in bewilderment as the sheet draped over his piles of books and homework; he glanced down and all the blood drained from his face before he jerked away.

"Gregory--"

"HE'S GONE! SCABBERS IS GONE!"

John looked at the sheet, there was something red on it, and it looked a lot like--

"BLOOD! THAT'S RIGHT, JOHN! AND DO YOU KNOW WHAT WAS ON THE FLOOR?"

Greg threw a fistful of long, ginger, cat hair in Mycroft's stunned face.

 

It looked like the end of Greg and Mycroft's friendship. 

Greg was enraged that Mycroft had never taken Crookshanks's attempts to eat Scabbers seriously--and was now defending Crookshanks's innocence. 

Mycroft, after getting over the initial shock of a screaming Greg and bloody sheets being thrown over his homework, tutted disdainfully at the idea of Crookshanks being the one to dispose of Greg's 'plague-infested, not technically allowed, _pet_.' He cited Greg's bias against Crookshanks, and noted that Crookshanks and Scabbers had been sharing a dorm, and a tower, and an entire castle, since September without Scabbers being more than occasionally picked-on by his 'nemesis.' Crookshanks wasn't about to make dinner of Greg's 'unappetizing rodent' when the kitchen supplied him with an abundance of other options.

And, moreover, Crookshanks's long fur, and the fur of many other Gryffindor cats, could be found everywhere in their tower.

John, who was inclined to side with Greg due to Scabbers very real disappearance, couldn't help but consider Mycroft's insistence that Crookshanks had not, in fact eaten Scabbers. Mycroft's argument had been delivered once, cordially, over breakfast, before he turned his complete attention to a large stack of strawberry and cream covered waffles (Greg's following explosion shook the Great Hall, but failed to elicit any response from Mycroft beyond his asking Dean Thomas to please pass the pumpkin juice).

"He's probably right, you know," John said, as Greg followed him down to quidditch practice. 

"Who?" Greg had his hands shoved deep into the pockets of his robes, a gloomy frown on his face.

"Mycroft--wait, hear me out!" John grabbed Greg's arm before he could stalk off. "Mycroft's got absolutely no reason to lie about his, admittedly awful, cat. And the evidence, Greg, you're basing your accusation on _cat hairs_. _Dean_ has a cat too, and Molly's spends more time--"

"You are actually siding with Holmes on this?" Greg looked incredulous.

"Mycroft is my friend, Greg, I have to at least consider--"

"I'm your friend too, John! I was your friend _first_! Don't I get some consideration?" 

John froze. "You don't get to be right and choose my opinions for me just because you met me first, that's not how being friends works."

"But Holmes can manipulate you all he wants?"

"Mycroft isn't manipulating me, I'm _choosing_ to believe his side of the story because it's a sight more rational than yours!"

Greg sneered, "Merlin, but you're thick! Holmes has every reason to lie if he gets to keep you as his _friend_. Wake up, John, he's using you!"

John clenched his jaw around a small smile and shifted the Firebolt against his shoulder, the golden letters glittering accusingly at Greg. 

"I should get to practice--I'll see you in class, Lestrade."

 

The day of Gryffindor's match against Ravenclaw bore no resemblance to storm they'd faced against Hufflepuff, and despite the lingering memory of his row with Greg, John was very nearly giddy with anticipation, and he took to the air grinning. 

John had not failed to notice Ravenclaw's very pretty Seeker, Soo Lin Yao, who was the only girl on their team. She kept smiling at him, it was mildly distracting, actually. Soo Lin seemed to be tailing him around the pitch, occasionally cutting across him and forcing him to change directions. She was an impressive flier.

"Stop ogling, John! Show her what you can do!" Fred shouted as he wooshed past him in pursuit of a Bludger.

John shook himself, this was no way to win the match. He surged forward, his eyes peeled for the snitch--there! He dived, hurtling toward the ground at amazing speed, he was only a few feet away when he was forced to swerve away, where had that Bludger come from? 

Cursing, John soared high over the pitch once more, watching as Ravenclaw brought the score to 80-30, only fifty points behind Gryffindor now. 

The Snitch was circling one of Gryffindor's goal posts, and John zoomed towards it, only to have Soo Lin pull up in front of his broom, smiling brightly as the Snitch disappeared once more.

Wood was yelling something John didn't hear--if Soo Lin wanted to play this game, she'd need a much faster broom. John grinned back at her before diving again, and, just as he'd suspected she would, Soo Lin followed. John pulled out of the dive sharply, spinning and twisting across the field--he could hear her laughing far behind him. 

There was the Snitch again! Far above the Ravenclaw end; John accelerated, racing towards the Snitch with Soo Lin somewhere behind him. He was nearly there--

"Oh!" Soo Lin screamed, pointing down.

John looked, distracted, to see three dementors staring up at him.

He didn't even think. John pulled out his wand and roared, " _Expecto Patronum_!"

The party in the common room went on through the rest of the day, and well into the night. Moriarty's trick served only to heighten John's festive mood, as he pictured him and his goons in a crumpled heap on the pitch, tangled in their long black robes.

John sat for a while with Mycroft towards the end, who somehow managed to be both festive _and_ studious. John munched on Bertie Bott's Every Flavoured Beans and slung an arm casually around Mycroft, who had a heavy tome in his lap, and a bottle of butterbeer in one hand.

"Impressive flying today, John, despite your many distractions," Mycroft's smile implied that he didn't at all mean Jim Moriarty's attempt at frightening John off his broom.

"Ah, er..." 

John turned an interesting shade of red.

"Your audience seemed to appreciate your showing off," Mycroft continued, smirking mischievously. "Myself included."

John squawked, yanking his arm back to himself. Mycroft laughed, his head falling against the back of the sofa they'd settled on. 

"I'm sure I'm too young for that sort of thing," John said adamantly, blushing fiercely.

"So if Soo Lin Yao came up to you at lunch tomorrow--"

John pelted Mycroft with his remaining Bertie Bott's until Professor McGonagall turned up in a tartan dressing gown and a hair net, insisting they go to bed at once.

Greg was already asleep when John, Mycroft, Dean and Seamus staggered into their dorm well after one in the morning, each of them falling into their beds and swiftly drifting off to sleep. 

John woke up to a very loud and long yell, and Seamus's groggy, "What's going on?"

The dormitory door slammed, and he ripped open his curtains as Dean lit his lamp.

Greg was sitting up in bed, the hangings torn to one side, and terror etched onto his face.

"Black! Sirius Black! With a knife!"

**Author's Note:**

> Eh. I have no idea. Greg and John just started shouting, and Mycroft refused to be bothered. But I kind of like it. It gave me ideas for GoF.
> 
> And light Johncroft vibes. Y'know what? Let's see how many ships I can insert into this ridiculous hobby fic, eh?


End file.
